Guillaume Filion <[EMAIL PROTECTED]> wrote: > It might be simpler to make an SMTP connection to the MX RR of > the sender's domain, and maibe even do a MAIL FROM: <>, RCPT TO: > $senderAddress to do a simple address check. > > If the sender's SMTP server is not available, we can return a > temporary error code.
Aagh, no! That's what Verizon seems to be doing nowadays, and it's leading to larger mail queues everywhere. And what happens if the SMTP server you're trying to connect to wants to do the same thing? That way lies madness, perhaps not the level of madness of challenge-response systems, but madness nonetheless. -- Keith C. Ivey <[EMAIL PROTECTED]> Washington, DC
